This invention relates generally to cooling systems for data centers. More particularly, the invention pertains to a smart cooling system for delivering controlled amounts of cooling fluid, e.g., air, to various areas of a data center.
A data center may be defined as a location, e.g., room, that houses numerous printed circuit (PC) board electronic systems arranged in a number of racks. A standard rack may be defined as an Electronics Industry Association (EIA) enclosure, 78 in. (2 meters) wide, 24 in. (0.61 meter) wide and 30 in. (0.76 meter) deep. Standard racks may be configured to house a number of PC boards, e.g., about forty (40) boards, with future configurations of racks being designed to accommodate up to eighty (80) boards. The PC boards typically include a number of components, e.g., processors, micro-controllers, high speed video cards, memories, semi-conductor devices, and the like, that dissipate relatively significant amounts of heat during the operation of the respective components. For example, a typical PC board comprising multiple microprocessors may dissipate approximately 250 W of power. Thus, a rack containing forty (40) PC boards of this type may dissipate approximately 10 KW of power.
The power required to remove the heat dissipated by the components in the racks is generally equal to about 10 percent of the power needed to operate the components. However, the power required to remove the heat dissipated by a plurality of racks in a data center is generally equal to about 50 percent of the power needed to operate the components in the racks. The disparity in the amount of power required to dissipate the various heat loads between racks and data centers stems from, for example, the additional thermodynamic work needed in the data center to cool the air. In one respect, racks are typically cooled with fans that operate to move cooling fluid, e.g., air, across the heat dissipating components; whereas, data centers often implement reverse power cycles to cool heated return air. The additional work required to achieve the temperature reduction, in addition to the work associated with moving the cooling fluid in the data center and the condenser, often add up to the 50 percent power requirement. As such, the cooling of data centers presents problems in addition to those faced with the cooling of racks.
Conventional data centers are typically cooled by operation of one or more air conditioning units. The compressors of the air conditioning units typically require a minimum of about thirty (30) percent of the required cooling capacity to sufficiently cool the data centers. The other components, e.g., condensers, air movers (fans), etc., typically require an additional twenty (20) percent of the required cooling capacity. As an example, a high density data center with 100 racks, each rack having a maximum power dissipation of 10 KW, generally requires 1 MW of cooling capacity. Air conditioning units with a capacity of 1 MW of heat removal generally requires a minimum of 300 KW input compressor power in addition to the power needed to drive the air moving devices, e.g., fans, blowers, etc. Conventional data center air conditioning units do not vary their cooling fluid output based on the distributed needs of the data center. Instead, these air conditioning units generally operate at or near a maximum compressor power even when the heat load is reduced inside the data center.
The substantially continuous operation of the air conditioning units is generally designed to operate according to a worst-case scenario. That is, cooling fluid is supplied to the components at around 100 percent of the estimated cooling requirement. In this respect, conventional cooling systems often attempt to cool components that may not be operating at a level which may cause its temperature to exceed a predetermined temperature range. Consequently, conventional cooling systems often incur greater amounts of operating expenses than may be necessary to sufficiently cool the heat generating components contained in the racks of data centers.
According to one aspect, the present invention pertains to a smart cooling system for cooling racks in a data center. The system includes a cooling device for supplying cooling fluid to the racks. The cooling device includes a variable output fan and a variable capacity compressor. The system also includes a plenum having an inlet and a plurality of outlets, in which the inlet of the plenum is in fluid communication with the fan. A plurality of vents for delivering the cooling fluid to the racks is also included in the system. The vents are operable to vary a characteristic of the cooling fluid delivered through each of the vents.
According to another aspect, the present invention pertains to a method of cooling a plurality of racks in a data center. In the method, a cooling system is activated and a plurality of vents are opened. Each of the vents is configured to supply cooling fluid to at least one of the racks. The temperatures of each of the racks are sensed and it is determined whether the sensed temperatures are within a predetermined temperature range. In addition, the supply of the cooling fluid to the racks is varied in response to the sensed temperatures.
According to yet another aspect, the present invention relates to a data center housing a plurality of racks. The data center includes a raised floor having a plurality of vents and a plenum located beneath the raised floor. The data center also includes a cooling system having a variable capacity compressor and a variable output fan and the cooling system is configured to supply a cooling fluid into the plenum. The plenum is in fluid communication with the plurality of vents which are configured to deliver the cooling fluid to the racks. The vents are operable to vary a characteristic of the cooling fluid delivered through each of the vents. A divider is positioned within the plenum and operates to divide the plenum into a first chamber and a second chamber. The first chamber of the plenum is in fluid communication with the cooling system and the second chamber is in fluid communication with the vents. The divider operates to maintain the pressure of the cooling fluid in the second chamber at a substantially uniform pressure. The data center further includes at least one vent controller operable to control at least one of the vents. The at least one vent controller is configured to independently control the vents to thereby independently vary the characteristic of the cooling fluid flow through the vents. In addition, the data center includes a cooling system controller operable to control a speed of the compressor and an output of the fan to thereby vary the output of the cooling fluid from the cooling system to thereby vary the cooling fluid supply in the plenum.
In comparison to known data center cooling mechanisms and techniques, certain embodiments of the invention are capable of achieving certain aspects, including some or all of the following: (1) substantially focalized supply of cooling fluid to individual racks; (2) substantially independent control of the fluid supply to the racks; (3) energy efficient utilization of a cooling system by operating them substantially only as needed; (4) cooling fluid supply may be individually varied in accordance with actual or anticipated temperatures of the heat generating components; and (5) the costs associated with operating the cooling system of the invention may be substantially lower than with operating conventional cooling systems. Those skilled in the art will appreciate these and other benefits of various embodiments of the invention upon reading the following detailed description of a preferred embodiment with reference to the below-listed drawings.